Q-Jet Follies

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I haven't had major ignition issues, but I've sure had a lot of reliability issues - CATOs of various manifestations. Some made it off the pad, other just blew on the pad. The E26's have been the main offenders for me. Here's my Lil' Nuke which barely cleared the rod before turning into a Roman Candle.

View attachment 609118
🎼Watch out where those Q-Jets go, don't you eat that ebony snow.
 
So ...

I just last week received one-pack each D22-10W ( Batch 052221-01 ), E26-10W ( Batch 033123 ) and E35-11W ( Batch 051723 ).

Are the problems described in this thread limited to the E26 Q-Jet or are all of them subject to the same caveats ?

Thanks

-- kjh
Reportedly, the Q-jets from Nov 2021 and before used a clay formulation that deteriorated in humid environments. They glued something llke a washer on the ends to contain the clay. The new formulation has black clay.

I'm going to try scoring the inside with a paper clip before launching.

Just so you know, the Quest 10 second delay is a slow 10 second delay so use a really fast rocket so it doesn't lawn dart or use a rocket that spins like a Vortico.
 
Reportedly, the Q-jets from Nov 2021 and before used a clay formulation that deteriorated in humid environments. They glued something llke a washer on the ends to contain the clay. The new formulation has black clay.

I'm going to try scoring the inside with a paper clip before launching.

Just so you know, the Quest 10 second delay is a slow 10 second delay so use a really fast rocket so it doesn't lawn dart or use a rocket that spins like a Vortico.
Thanks @Ronz Rocketz !

Good info about the color of the Clay.

All of mine have light grey clay nozzles that look like Estes BP nozzles.

As for delays ...

Now that I have a Blue Raven instead of an AltAcc, I can finally fly an AV-Bay and dual deployment in any rocket, 29mm or larger where I've got 4.25 inches available for the coupler + bulkheads and room for a main chute.

These motors were all for flying in "La Pequeña Vulcanita 34" -- a glassed, dual deployment, 200 gram BT-55 Scale Model of a LOC Vulcanite.

I'll be removing the BP from the Ejection Charge Well and flying a streamer at apogee and a 12-in main at 500 ft or so, depending on the apogee altitude.

I like the extra smoke past apogee so I always try to buy the longest delay available for rockets with electronic deployment.

And I can't wait for a waiver and a site and a weather forecast, and maybe a little 'Go Fever' where I can fly an RMS 29/360 I200-14W in her :)

-- kjh

EDIT: p.s. I might even be able to squeeze a Blue Raven + Simple Circuit + Mag Switch in a BT-50 ... at least I hope so ...

If not, maybe I'll find a Featherweight 24mm Av-Bay that needs a good home :)
 
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Just wondering about how the Q-Jets with ignition problems are being stored. How the vendors store them is beyond anybody's control and most likely not in an air-conditioned room. High humidity is not good especially for the WL motors. I have single use and reloads 20 + years old that are always stored in an air conditioned room with never more than 50% RH. Never have a problem when using one.
I keep all my motors - RMS and SU in both MPR and HPR flavors - in the same room. This room is on the lower level of my house and consistently stays around 68-70F with humidity between 20-40% depending on the time of year. Motors stay in the unopened OEM packaging until they're ready for use. Once I open MPR RMS multi-packs I place the unused items inside a zip lock bag. The only difference in how I store motors is the OEM packaging. Typing this message has made me realize I could start storing my SU motors in zip lock bags. Not sure if that would make much of a difference but zip lock bags are cheap so why not try that.
 
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While we are investigating, if you have any 2021 lot codes that have nozzle swelling or motors that won’t ignite, please send a photo and details to warranty and we will replace those. Customers in dry climates probably won’t experience that issue.
 
Just a thought here. What about vacuum bag sealing with the little desiccation packet to control moisture exposure? Yes, I know increase’s the cost.
 
Reportedly, the Q-jets from Nov 2021 and before used a clay formulation that deteriorated in humid environments. They glued something llke a washer on the ends to contain the clay. The new formulation has black clay.
That reminds me of the old Pro-Jet motors from the 80's. It seemed that every new motor manufacturer wanted to make a more reliable motor, but ended up making them as cheap as possible. They used some white cast material for the aft closure and nozzle. They discovered that by embedding a steel washer at the throat, and grinding an attractive nozzle exit and end, that it would work well enough, and was cheaper than machined graphite nozzles. Later they discovered that they could just use the raw unfinished white cast material with a straight hole through the washer and the motor exhaust would form a suitable exit cone. I flew many of those E20 and F45 motors until an E20 totally torched my Maxi Alpha.
 
I've got all my recently purchased, unopened motor packages in a container store box on a bed of kitty litter (*) until I can get around to buying a few more Ruggard Silica Gel Desiccant Packs...

All my infamous 25-year old motors are already stored with neglected but recently 'baked' Silica Gel Desiccant Packs but it may be too late for them ...

-- kjh

(*) - unused kitty litter, that is :)
 
Anyone else having this problem with E26Ws? Not minor chuffing at ignition but heavy chuffs and failure to ignite?
The FirstFire Jr. ignitor will light it OK. This motor previously would not ignite with the supplied micro ignitor. But I am not going to be buying any more E26s expecting to buy the bigger ignitors or mess with "enhancing" the ones supplied.

Even if ignition was not a problem, the chuffing is. I would call this a heavy chuff. Could be unsafe if the rocket fell off the rod after the chuff.

 
What was the lot number?
The FirstFire Jr. ignitor will light it OK. This motor previously would not ignite with the supplied micro ignitor. But I am not going to be buying any more E26s expecting to buy the bigger ignitors or mess with "enhancing" the ones supplied.

Even if ignition was not a problem, the chuffing is. I would call this a heavy chuff. Could be unsafe if the rocket fell off the rod after the chuff.

 
My experience with E26 has been one failure, but many good launches. Even with the failure, where I went through 3 ignitors trying to get it to launch, I was able to take the motor back home, scrape it (CAREFULLY) with a small wire brush through the nozzle to clean out the residue, and then I was able to fire that motor successfully at the next launch. I was using a gun-cleaner brush meant for a .22, which was the smallest I could find. Actually I think it's for a pellet gun. Not sure.

Now, let it be noted that I am NOT using the Q-picks. I just store those in my tackle box. I use regular old masking tape to hold the ignitor in place and that works great for me. Those E26 motors do chuff, and if they spit out the ignitor, you're done for the day with that motor unless you can scrape it on the inside to remove any carbonization that may have built up during the chuff.

The Aerotechs with the plastic nozzle seem to be more reliable than the Q-jets with the clay nozzle, but the Aerotechs cost more. (or at least, that's been my experience). Still the Q-jets are great bang for the buck, and they work flawlessly most of the time.
 
We are looking at these issues.

Regarding the “black clay”, the clay hasn’t changed from the material being used this year. The new F41Ws will use a black phenolic nozzle.
Sorry, I meant to say the modified motors with the clay caps are black. I've used up all of mine so don't have a photo. The 18mm motors that Karl graciously mailed to me are grey and dated 2023. I do have two E26 motors dated 2022, but I'm hesitant to put them in anything I cherish.

My Conquest fortunately survived a heavily chuffed D20. This seems to be happening more and more. I killed my Venus Probe last week but that's my fault for using a D16 dated 2021. The motor didn't fully engage until the end of the rod just like the Conquest.

 
I had another E26-4W (date code: 052621) cause problems yesterday. It chuffed and chuffed and eventually BARELY cleared the rod, falling over to chuff more and then eject in nearby grass. The nozzle looked pretty blown out after, as well (see pic comparing to a well-flown nozzle). The other motor in this package flew fairly well.
 

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Sure sounds like there is a problem. Hopefully, Quest Aerotech had it figured out.
 
I had another E26-4W (date code: 052621) cause problems yesterday. It chuffed and chuffed and eventually BARELY cleared the rod, falling over to chuff more and then eject in nearby grass. The nozzle looked pretty blown out after, as well (see pic comparing to a well-flown nozzle). The other motor in this package flew fairly well.

Here is one of my earlier posts, in another thread. It is from information either from the forums, or correspondence with AT.
AT changed the Formulation of the Nozzles in 8/21. Any lot Numbers prior to that were at higher risk depending on storage conditions, as the original clay was subject to moisture absorption, and could get "soft".

If the 8/21 date of the change IS CORRECT... Then your 052621 manufactured motor, is from JUST BEFORE the material change.

Everyone PLEASE check date/lot code, IF YOUR COMPLAINING ABOUT A MOTOR BEFORE 8/21, IT'S A KNOWN AND ADDRESSED ISSUE.

likewise, IF your having issues with lot codes after 8/21, then for sure list the lot code, with the complaints.

[I'll get off the soapbox now. I just want to separate, old vs new issues.]
 
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Here is one of my earlier posts, in another thread. It is from information either from the forums, or correspondence with AT.


If the 8/21 date of the change IS CORRECT... Then your 052621 manufactured motor, is from JUST BEFORE the material change.

Everyone PLEASE check date/lot code, IF YOUR COMPLAINING ABOUT A MOTOR BEFORE 8/21, IT'S A KNOWN AND ADDRESSED ISSUE.

likewise, IF your having issues with lot codes after 8/21, then for sure list the lot code, with the complaints.

[I'll get off the soapbox now. I just want to separate, old vs new issues.]
AT told me the formulation changed in 11/21 but I think anything in 2021 and before is suspect.

Indeed, the chuffing off the rod is a new issue. My solution is to stick a 1cm piece of cannon fuse in the 24mm motors with the initiator. My theory is the fuse will kick it into gear if it starts chuffing. No way I can think of to test this because it's difficult to tell which motor will chuff and which will ignite.

It appears my Doorknob with the F67-6C didn't need the fuse and pushed it out with no chuffing. (Side note: my cam has artifacts from 45sec to 1:45 but might be only one cam doing this. If you squint, you can see the fuse half lit.)

1698642462943.png
 
Launched the E26-4W (092722-01) yesterday. No problems with nozzle clay but lots of rod chuffing. For the second attempt, I added 1cm cannon fuse to the E26 (after scoring the inside with a paperclip). I should say the C12-4FJ (020123-04) worked great.



What's surprising is probable air chuffing of the F67-6C (030923) when the chuffing started about 30ft in the air. There were three puffs of smoke before taking off. In the flight video and graph, you can see the velocity jumping around (more than usual) before the rocket took off.

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So for educational purposes, which motor is the best chuff demonstrator?
 
So for educational purposes, which motor is the best chuff demonstrator?
This video.... only comical because no injuries, or damage to anything; other than the blast deflector, and the rocket.

But from an educational purpose this is the ultimate chuff.

(FYI... I heard they knew it was an OLD motor, were ready for some "issues", and was definitely a "heads up flight" with everyone watching just in case...but they still got more show than expected.)

 
For kicks, I disassembled a C18 that I couldn’t get to start. I was surprised to see a cored grain, rather than a C-Slot. Given the small nozzle, and the limited amount of pyrogen to fit through the nozzle, it’s not surprising they’re hard to start, as the pyrogen may not be touching the grain, just the delay.
 
Launched the E26-4W (092722-01) yesterday. No problems with nozzle clay but lots of rod chuffing. For the second attempt, I added 1cm cannon fuse to the E26 (after scoring the inside with a paperclip). I should say the C12-4FJ (020123-04) worked great.



What's surprising is probable air chuffing of the F67-6C (030923) when the chuffing started about 30ft in the air. There were three puffs of smoke before taking off. In the flight video and graph, you can see the velocity jumping around (more than usual) before the rocket took off.

View attachment 613124


Nice Plot, Ron !

You can see the chuffs very clearly !

What flite computer are you running ?

Thanks

-- kjh
 
This video.... only comical because no injuries, or damage to anything; other than the blast deflector, and the rocket.

But from an educational purpose this is the ultimate chuff.

(FYI... I heard they knew it was an OLD motor, were ready for some "issues", and was definitely a "heads up flight" with everyone watching just in case...but they still got more show than expected.)


That is one of the best videos I've ever seen of a launch, or sort of a launch. Definitely an Oscar nomination for production, editing, audio, sound track, and actor!
 
Eggtimer Ion. You mean the chuffs in the graph or the video or both?
Both !

But I was confused ... I mis-remembered which data plot went with which flight video ...

I remembered seeing the E26 in the red rocket with the ring fins chuff on the pad and then in the air but that was an E26, not an F67-C

So I watched again at 1/4 speed ...

At about 4:10, the red rocket with ring fins on an E26 chuffed in the video the second time with the canon fuse enhancer.

Starting at 6:03, I didn't see the F67 chuffing in the slo-mo video but you can sure see where the motor almost snuffed in mid-air in your spooky music data plot !

I still didn't see the motor chuffing in the video even in slo-mo ... but that classic Enerjet propellant leaves very little smoke trail ...

How did you get it down from the roof of the graphics shop ?

Did you ask them to make some you some stickers ? :)

Thanks Ron, I watch for your posts and then I like to grab a snack to watch your videos :)

-- kjh
 
Both !

But I was confused ... I mis-remembered which data plot went with which flight video ...

I remembered seeing the E26 in the red rocket with the ring fins chuff on the pad and then in the air but that was an E26, not an F67-C

So I watched again at 1/4 speed ...

At about 4:10, the red rocket with ring fins on an E26 chuffed in the video the second time with the canon fuse enhancer.

Starting at 6:03, I didn't see the F67 chuffing in the slo-mo video but you can sure see where the motor almost snuffed in mid-air in your spooky music data plot !

I still didn't see the motor chuffing in the video even in slo-mo ... but that classic Enerjet propellant leaves very little smoke trail ...

How did you get it down from the roof of the graphics shop ?

Did you ask them to make some you some stickers ? :)

Thanks Ron, I watch for your posts and then I like to grab a snack to watch your videos :)

-- kjh
Awesome. Thanks for watching.

The F67C was a head scratcher. Per the graph, the rocket flew to about 100ft, wobbled around a bit, chuffed three times, and took off fortunately in an upward direction. Of course, this all happened in a second, so hard to see in the video or in my memory what happened. To me, it looked like it was doing flips. I notice the chuffing while watching the video.

1699480287968.png

We were joined by three teens who told us the school was closed because of a water main break. My son and the teens ran to find the rocket. The home owner placed his ladder and one of the teens climbed on the roof to retrieve it. There were a series of fortuitous events that led to the rocket recovery. I doubt I would've been able to get it by myself.
 
We were joined by three teens who told us the school was closed because of a water main break. My son and the teens ran to find the rocket. The home owner placed his ladder and one of the teens climbed on the roof to retrieve it. There were a series of fortuitous events that led to the rocket recovery. I doubt I would've been able to get it by myself.
In my younger days I recovered a rocket from the roof of a high school by climbing up onto some old lockers and jumping up on the roof..... rocket follies.​
I figured I could talk my way out of it... :dontknow:
 
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